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 A096831 Number of primes in the neighborhood with center = n-th primorial and radius = ceiling(log(n-th primorial)). 1
 2, 2, 2, 1, 2, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS What is exceptional in such neighborhoods of primorials is that in most cases no primes occur, i.e., these zones are peculiarly poor or empty of primes! Primes are scarce in these zones because log(A002110(n)) < prime(n), so A002110(n)+1 and A002110(n)-1 are the only numbers in the neighborhood that are not divisible by one of the first n primes. - David Wasserman, Nov 16 2007 LINKS FORMULA a(n) = A096509(A002110(n)). EXAMPLE n=7: 7th primorial=510510; radius=14, a(7)=0 because there are no primes in the relevant neighborhood. [1, 3], [4, 8], [26, 34], [2302, 2318] (around 2, 6, 30, 2310, respectively) are the only zones in which 2 primes were found. CROSSREFS Cf. A096509-A096523, A002110. Sequence in context: A129320 A320844 A212119 * A191516 A168141 A232654 Adjacent sequences:  A096828 A096829 A096830 * A096832 A096833 A096834 KEYWORD nonn AUTHOR Labos Elemer, Jul 14 2004 STATUS approved

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Last modified August 9 21:08 EDT 2022. Contains 356026 sequences. (Running on oeis4.)